1.6 Properties of addition

Use the commutative property of addition to find the sum of 12 and 41 in two different ways.

Add the whole numbers

Use the associative property of addition to add the following whole numbers two different ways.

$(\text{11}+\text{27})+9$ and $\text{11}+(\text{27}+9)$

$(\text{80}+\text{52})+6$ and $\text{80}+(\text{52}+6)$

$(\text{114}+\text{226})+\text{108}$ and $\text{114}+(\text{226}+\text{108})$

$(\text{731}+\text{256})+\text{171}$ and $\text{731}+(\text{256}+\text{171})$

The fact that (a first number + a second number) + third number = a first number + (a second num­ber + a third number) is an example of the property of addi­tion.

The fact that 0 + any number = that particular number is an example of the property of addi­tion.

The fact that a first number + a second number = a second number + a first number is an example of the property of addi­tion.

Use the numbers 15 and 8 to illustrate the com­mutative property of addition.

Use the numbers 6, 5, and 11 to illustrate the associative property of addition.

The number zero is called the additive identity. Why is the term identity so appropriate?

( [link] ) How many hundreds in 46,581?

( [link] ) Write 2,218 as you would read it.

( [link] ) Round 506,207 to the nearest thousand.

( [link] ) Find the sum of $\begin{array}{c}\hfill 482\\ \hfill \underline{+\mathrm{ 68}}\end{array}$

( [link] ) Find the difference: $\begin{array}{c}\hfill \mathrm{3,318}\\ \hfill \underline{-\mathrm{ 429}}\end{array}$